Well, then, why not just create a separate felinoid warrior race? It's not like the Kzinti are the only such species in SF by a long shot. So if you're going to separate them from their Nivenian elements, they're not Kzinti at all, just Felinoid Warrior Alien Race #47.

Folks may recall that we at Star Trek Phase II had started pre-production on Jimmy Diggs' Kzinti script--adapted to a Kirk-era story. We were stymied by not being able to secure the production rights to the Kzinti from the gentleman to whom Larry Niven sold them years ago. We started to forge ahead with the felinoid race being called the "Kytheri." Ultimately, there were just too many obstacles to overcome and we had to backburner (way backburner) to episode.